So we use OP277 and OP77B both of which are in the discontinuation phase. Although both will end production in Oct 2014, Siemens makes a big point of service and spare parts being available until Oct 2022. Sounds good. Makes one think there's plenty of time (years), to make the migration. BUT, I've sent at least 4 OP277's for repair. NOT ONCE, have I actually received a repaired unit back. It's always been a case of it's not worth repairing, or some other reason - we'll replace the unit for only X dollars, which is about half the price of simply buying a unit without exchanging one. So, do I really have until 2022, or am I actually going to have a problem when I run out of spares in a couple of years? Will I find myself receiving a KP700 comfort panel instead of an OP277? When should I start hitting this, as it requires re-programming of the K keys, and different software (WinCC v WinCC flexible).